Ratchet jack-screw.



B-ATENTED SEPT. 4, 1906.

. G. H. JACK.

RATGHET JACK SCREW, APPLICATION FILED MAB. 1, 190a.

INVENTOR C/mr/es Hu er? L/a'c/L WITNESSES: I? Z. JW J Mk Nrrn CHARLES HERBERT JACK, OF POUGHKEEPSIE, NEXV YORK.

RATCHET JACK-SCREW.

Specification of Letters Patent.

Patented Sept. 4, 1906.

Application filed March 1, 1906. Serial No. 303.589.

To (fl/U 11:71.07 it 717/07 concern:

Be it known that I, CHARLES HERBERT JACK, a citizen of the United States of Amer ica, residing at Poughkeepsie, in the county of Dutchess and State of New York, have invented certain new and useful Improvements in Ratchet J ack-Screws, of which the following is a specification.

This invention relates to improvements in ratchet jack-screws and other lifting devices of like nature.

The object of this invention is to provide a simple, strong, efficient, and inexpensive ratchet jack-screw that is capable of being used in corners or close to a wall, owing to the use of a ratchet to work the lifting-screw. The advantage of this over the present design of jack-screw will be seen at a glance.

\Vith this and other objects in view, which will appear as the nature of the invention is better understood, the same consists of certain novel features of construction, combination, and arrangement of parts, as will be more fully described and claimed in the following specification and claimsv In the drawings, Figure 1 is a side elevation. 2 is a vertical section through the center. Fig. 3 is a plan view, and Fig. 4 is a section on the line a b in Fig. 2, showing the ratchet in detail.

In the embodiment of my invention illustrated in the drawings the numeral 1 denotes a cast iron or steel body or standard of the usual form, which is screw-thre aded at its upper end to receive the threaded end of the lifting-screw 2. Said lifting-screw is slightly turned down or reduced in diameter near its upper end to form the shoulder 17, which supports the ratchet-case 3 and also the toothed sleeve at, which is rigidly secured to the lifting-screw by the pin 13, while the ratchet-case 3 has a free circular motion around the lifting-screw 2 and the toothed sleeve 4, except as governed by the pawls 9 and 9, as desired.

The pawls 9 and 9 are pivoted by the pins 12 in the slot 18, which extends from side to side*of the case 3, and said pawls are held with their engaging points in contact with the teeth 16 on the sleeve 4 by the spring 11.

The knurled ring 7, which is held in place on the case 3 by the pins 8, (allowing it to turn freely between them,) is partly cut away on the side next the pawls for a little over half its circumference. The pins 8 being set at its narrowest part, they only allow of its being turned a little over onehalf a revolution in either direction. Thus when it is turned in either direction until the projection of the wider side comes in contact with the pin 8 it will be brought into such a position that the wide side will be over the rear end of one pawl, forcing' the rear end of the pawl in, thus disengaging its point from the teeth of the toothed sleeve 4, while the other or narrow half of the ring 7 will be on the other side of the case 3, allowing the rear end of the pawl on that side to be freed and forced outward by the spring 11. This brings the point of the pawl 9 into engagement with the teeth 16 on the sleeve 1, and so if the ratchet-case is forced by the rod 14 in a direction away from the pawl that is released at its rear end by the rotation of ring 7 the released pawl will freely pass over the ends of the teeth 16, while if the case is forced in the opposite direction the point of the pawl which has been released, as before described, by the rotation of the ring 7 will engage a tooth of said sleeve and hold it firmly, thus turning the lifting-screw 2.

If the ring 7is turned in the opposite direc tion, the pawl that was held will be released and the other one engaged, which will reverse the action of the ratchet and work the lifting-screw in the opposite direction.

The end of the case 3 is provided with the hole 15 to receive a removable bar or rod 14 to act as a handle.

The cap 5 is held in place by the washer and screw 6, thus allowing it to rotate freely, giving the lifting-screw a freer movement.

From the foregoing description, taken in connection with the accompanying drawings, it is thought that the mode of using the illvention and the many advantages thereof will be readily understood without more ex tended explanation.

Various changes in the form, proportion, and minor details of construction may be r sorted to without departing from the principle of the invention.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. The combination with a jack-screw lifting-rod, of a ratchet-case, rotating on a shoulder forming part of said rod, and provided. with two pawls pivoted into slots in opposite sides of said case, a toothed sleeve seating in said case and secured to said rod and means whereby the pawls can be thrown in or out of ITO engagement with the teeth of said sleeve said means comprising a knurled ring slipped over the end of said case and held in place by guide-pins, substantially as described and for the purpose set forth.

2. The combination with a lifting-screw and a ratchet-case mounted on said screw, of two pawls pivoted midway their ends in slots contained in the sides of said case, and having their rear ends forced apart by a spring, and provided with means for securing the rear end of one pawl and releasing the rear end of the other as desired, said means comprising a knurled ring surrounding the end of said case and held in place by guide-pins, said guide-pins being arranged one at each edge of the ring and said ring being provided with a projection on one side extending around about one-half of its circumference, and extending over and retaining the rear end of pithlelr pawl as desired, for the purpose set ort 3. In a jack-screw, the combination with a threaded standard and a lifting-screw, said screw having a shoulder above its threaded portion, of a toothed sleeve mounted on the said screw above said shoulder, a pin passing through said sleeve and through said screw, said sleeve having a shoulder near its upper end, a ratchet-case mounted on the shoulder on the screw, and partly surrounding said sleeve and bearing at its upper edge against the shoulder of the sleeve, pawls mounted in said case and engaging the sleeve, and means for moving the pawls alternately into and out of engagement with the sleeve.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES HERBERT JACK. 

